Such rollers are used in general to maintain a constant tension on the belt or chain within a determined range or to modify locally the routing of the belt or chain. The terms tensioner roller and winding rollers, respectively, are used. In winding rollers, the pulley is mounted rotationally on a bolt or axle through the intermediary of a bearing, the roller then being attached directly or indirectly to the engine block or to a component of a tensioner roller device, for example an articulated or eccentric member. The bearing is any mechanical device enabling the operation of a pivot connection between the pulley and the bolt or axle, and to this end may be a rolling bearing or the like.
In general, a spacer is used in conjunction with the bolt or axle to attach the roller to its support. During installation, it is desirable for the axle or bolt to be axially attached to the other components comprising the roller and containing the pulley. This provides an assembly which cannot be dismantled, is easy to handle and transport and which may be installed easily.
To this end, a pulley device for a tensioner roller comprising a pulley, a bearing, a spacer supporting the bearing and a securing bolt that is axially immobilised in relation to the spacer is known from document FR 2 954 437. The relative axial engagement of the securing bolt and the spacer is achieved by means of a retaining ring arranged to engage with a groove cut into the securing bolt.
One disadvantage of this solution, inter alia, is that it requires a specific design for the securing bolt. Furthermore, a relatively large area must be left free on the frontal surface of the spacer to allow the installation of the retaining ring. The requirement reduces the contact surface between the spacer and its support considerably.
The aim of the present invention is to eliminate the disadvantages.